I am the proud new owner of erimille's HDT kit that he sold through the classifieds and am preparing to build. My question deals with material density and what is best for speaker integrity. I see that mdf is the usual material but it is not a good material in the tropics. I have a number of choices and would like to use the best one. MDX (exterior mdf), hdf (high density mdf-very heavy), Xterra (treated, waterproof mdf) and multi-ply dense baltic birch. Has anyone encountered real info about which is best for sonics? As a cabinetmaker I have the knowledge, machinery and skill as well as an assortment of materials. Am I being to anal or is there an overall best choice based upon material characteristics? mahalo in advance,

This is an ages old debate. In fact, from my internet experience over the last ten years or so, I would say it is the hottest debated topic in audio. I have built speakers out of every material from solid hard woods to MDF, to ply and even from composites of differnt woods and plastics and no few out of fiberglass.

There are scientists and salesmen, theoreticians (sp?) and builders who will all give you the reason why one is the best or at least better than another. I don't personally believe the material makes nearly as big a difference as some would have you believe. I think it makes a difference, but I don't necessarily think that means the difference is better from one to another.

My current speakers are built from Ply. One is from higher quality ply than the other. I can turn one off or the other and you cannot tell a difference between them no matter how good your ears are. I personally like particle board a little better than MDF and I know that no few "pros" build from a mish mash of materials. Some sides from ply, others from Particle or MDF. I think it dependds on your point of view more than the science. The thing is everything works together to create the end result. I would almost venture to look into the equipment you will be using, the room it is going in, and your taste in sound before I would say which is the best.

From experience I can tell you that the ply works extremely well for my HDT's and I am extremely happy with them.

Thanks Robert, I am leaning toward 13 ply Finnish birch (Baltic) and feel it is quite dense and rigid enough to handle anything. I really wish I had the ability to try a range of materials as a comparison effort. I know that mdf has certain characteristics that make it a natural choice but I would have to veneer every surface with epoxy glue to make it substantial enough for the tropical humidity. I plan to put some fancy veneer on the outside and use other woods as trim elements. The birch also has the plus of being quite machinable and stable. I will say that there's a range of opinion in audiophilia about what works best. I guess I will become another "expert". Thanks for your reply. mike

I know it's been a while, but I was wondering how your speakers turned out? I was also wondering if there was any possibility of building them out of real hardwood? I have been contemplating that with some new speakers I want to put together for my HT. I think my next set for pure listening are going to be built by Bob. I will keep my ideas to my HT as the quality isn't as important in there lol.

Bob, I am just building them now and taking photos at the same time. I ended up using Aquatek marine ply which is dense and waterproof with its epoxy glue between multi layers of ply(11 at my count). The exterior is quilted makore with a wenge lid on the lid/diffuser. I am a cabinet maker and a bit anal on the look so they will take a little to finish but I expect beauty in appearance and sound. I have a Torii MkII arriving in a couple days so I am feverishly pursuing the completion as I have nothing to drive them with and cant wait to hear them also. I will post when I get it all together. aloha, mike

P.S. Using solid wood for the box construction to my mind is a problem due to expansion/contraction of wood especially in the transmission line section of the HDT which could separate the corners of the box and create a leakage. Synthetic dense materials faced with veneer would normally be the best choice. mg